I distinctly remember a red dahlia in my Mum's strawberry patch when I was a child. We had to pass by it every day on the way through the garden to school. It was never more than a lush mound of foliage before the end of the summer term but, some time over the holidays, it would rear up commandingly and explode in colour. I loved its fleshy flamboyance, and the fact that it wasn't there one minute and then way above my head the next.

There is something about being small with access to a world that adults can no longer reach that, as a child, I recognised as my territory. I had hiding places beneath bushes in warm, dry nests of foliage and eyries in the forks of trees that grown-ups didn't know existed. There was a hollow in the roots of our beech tree that filled with water and, although no larger than a side plate, the life within it was a world in itself. Twitching mosquito larvae, rotting beech mast and bloated snails that had 'fallen' in held my attention for days.

At five I was propagating primrose seed in yogurt pots and making gardens on the roof of my self-styled mud and brick troll house. I liked the idea that I could fashion little worlds of my own from raw materials and, once I discovered the alchemy of growth, I was hooked. Soil, water and attention seemed to be all the ingredients required and, very soon, the roof garden of the troll house (and the trolls themselves) were usurped by beds of my own in the grown-up's garden.

I suppose that I responded most readily to things that showed immediate results to attention given. The amaryllis that transformed itself from a dry bulb to a glistening cluster of trumpets, the beans that split within days when they were placed in a saucer on damp tissue paper. The young shoots were already there in miniature and once in the soil they just kept going, breaking ground in an eruption at the base of the bamboo tower and racing away in a vigorous action, just like they did in the fairytale.

The courgettes and the pumpkins were just as fascinating, their first leaves filling out like sails in the sunshine. In no time, and like magic, there were the very same fruit that I recognised from the greengrocer's nestling in the shade under the bristly foliage. So this is where they came from!

Things that moved fast and fruited were the most rewarding initially, and I quickly learned to enjoy the process of growing tomatoes. The musty smell that hung about the plant when you brushed it, the speed at which the seedlings grew and the excitement of the first truss of flowers. Soon, at the base of each flower, was a miniature fruit that grew and grew, and I still remember the day that the first blush of tomato red completed the final product. That is until I realised that there were yellow tomatoes, too, and that they were just as easy.

The attention span of children may be short, but not so short that they can't start to see their efforts rewarded. A season is a long time to a child and, within a summer, there are several opportunities for them to witness the results. Vegetables allow them to see the whole process from scratch: how a bean grows into a pod, and how inside that silky pod there are more beans for the taking. A humble potato sprouted on a windowsill in February is in the ground over Easter and pushing through in a fortnight if the weather suits. The sprawl of foliage seems vast and endless to a child and the flowers come in no time. As an adult, forking out the first of the season's spuds is an incredible feeling, but as a child it is hard to believe that the wrinkled thing you put in the ground is responsible for the pale waxy tubers that have developed under the ground. Furthermore, it is hard to imagine that these are the very same things that chips and mash are made from.

Flowers also have their fascination, particularly those that show results in no time. The brighter the better seems to be the way to go, and there are few things easier than nasturtiums. Push a finger into the soil to make a hole just big enough to pop a seed into, pat the soil back into place and soon there will be a pair of perfectly circular leaves. On wet days, or after a dewy morning, each leaf holds a pristine jewel of water. There will be bees to pollinate the hooded flowers and ladybirds to eat the blackfly, and more seeds to collect if you lift up the foliage once summer is in full swing. Tagetes, calendula and morning glory are just as easy. You can count the flowers of ipomoea as they open every morning, and night-scented stock is worth trying simply because they produce perfume as well as fruit and flowers.

This summer my four-year-old niece started her first sunflowers, and when she returns from her summer holidays she will not believe how tall they have grown in her absence. I will also be planting some bulbs with her this autumn, after we have cut the flower heads off the sunflowers and hung them upside down outside the window for the birds. The wait might be a little longer, because a winter to a child is a lifetime, but before you know it the paperwhites and hyacinths will be fingering through the soil in readiness for the pots to be wrapped for the grandparents for Christmas.